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Delehedde C, Culcasi M, Ricquebourg E, Cassien M, Siri D, Blaive B, Pietri S, Thétiot-Laurent S. Novel Sterically Crowded and Conformationally Constrained α-Aminophosphonates with a Near-Neutral p Ka as Highly Accurate 31P NMR pH Probes. Application to Subtle pH Gradients Determination in Dictyostelium discoideum Cells. Molecules 2022; 27:molecules27144506. [PMID: 35889385 PMCID: PMC9320275 DOI: 10.3390/molecules27144506] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Revised: 07/10/2022] [Accepted: 07/12/2022] [Indexed: 11/16/2022] Open
Abstract
In order to discover new 31P NMR markers for probing subtle pH changes (<0.2 pH unit) in biological environments, fifteen new conformationally constrained or sterically hindered α-aminophosphonates derived from diethyl(2-methylpyrrolidin-2-yl)phosphonate were synthesized and tested for their pH reporting and cytotoxic properties in vitro. All compounds showed near-neutral pKas (ranging 6.28−6.97), chemical shifts not overlapping those of phosphorus metabolites, and spectroscopic sensitivities (i.e., chemical shifts variation Δδab between the acidic and basic forms) ranging from 9.2−10.7 ppm, being fourfold larger than conventional endogenous markers such as inorganic phosphate. X-ray crystallographic studies combined with predictive empirical relationships and ab initio calculations addressed the inductive and stereochemical effects of substituents linked to the protonated amine function. Satisfactory correlations were established between pKas and both the 2D structure and pyramidalization at phosphorus, showing that steric crowding around the phosphorus is crucial for modulating Δδab. Finally, the hit 31P NMR pH probe 1b bearing an unsubstituted 1,3,2-dioxaphosphorinane ring, which is moderately lipophilic, nontoxic on A549 and NHLF cells, and showing pKa = 6.45 with Δδab = 10.64 ppm, allowed the first clear-cut evidence of trans-sarcolemmal pH gradients in normoxic Dictyostelium discoideum cells with an accuracy of <0.05 pH units.
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Affiliation(s)
- Caroline Delehedde
- Aix Marseille Univ, CNRS, ICR, UMR 7273, SMBSO, 13397 Marseille, France; (C.D.); (M.C.); (E.R.); (B.B.); (S.P.)
| | - Marcel Culcasi
- Aix Marseille Univ, CNRS, ICR, UMR 7273, SMBSO, 13397 Marseille, France; (C.D.); (M.C.); (E.R.); (B.B.); (S.P.)
| | - Emilie Ricquebourg
- Aix Marseille Univ, CNRS, ICR, UMR 7273, SMBSO, 13397 Marseille, France; (C.D.); (M.C.); (E.R.); (B.B.); (S.P.)
| | - Mathieu Cassien
- Yelen Analytics, 10 Boulevard Tempête, 13820 Ensuès-la-Redonne, France;
| | - Didier Siri
- Aix Marseille Univ, CNRS, ICR, UMR 7273, CT, 13397 Marseille, France;
| | - Bruno Blaive
- Aix Marseille Univ, CNRS, ICR, UMR 7273, SMBSO, 13397 Marseille, France; (C.D.); (M.C.); (E.R.); (B.B.); (S.P.)
| | - Sylvia Pietri
- Aix Marseille Univ, CNRS, ICR, UMR 7273, SMBSO, 13397 Marseille, France; (C.D.); (M.C.); (E.R.); (B.B.); (S.P.)
| | - Sophie Thétiot-Laurent
- Aix Marseille Univ, CNRS, ICR, UMR 7273, SMBSO, 13397 Marseille, France; (C.D.); (M.C.); (E.R.); (B.B.); (S.P.)
- Correspondence: ; Tel.: +33-(0)4-13-94-58-07
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COVID-19, the Pandemic of the Century and Its Impact on Cardiovascular Diseases. CARDIOLOGY DISCOVERY 2021; 1:233-258. [PMID: 34888547 PMCID: PMC8638821 DOI: 10.1097/cd9.0000000000000038] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 09/19/2021] [Indexed: 01/08/2023]
Abstract
COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection likely ranks among the deadliest diseases in human history. As with other coronaviruses, SARS-CoV-2 infection damages not only the lungs but also the heart and many other organs that express angiotensin-converting enzyme 2 (ACE2), a receptor for SARS-CoV-2. COVID-19 has upended lives worldwide. Dietary behaviors have been altered such that they favor metabolic and cardiovascular complications, while patients have avoided hospital visits because of limited resources and the fear of infection, thereby increasing out-hospital mortality due to delayed diagnosis and treatment. Clinical observations show that sex, age, and race all influence the risk for SARS-CoV-2 infection, as do hypertension, obesity, and pre-existing cardiovascular conditions. Many hospitalized COVID-19 patients suffer cardiac injury, acute coronary syndromes, or cardiac arrhythmia. SARS-CoV-2 infection may lead to cardiomyocyte apoptosis and necrosis, endothelial cell damage and dysfunction, oxidative stress and reactive oxygen species production, vasoconstriction, fibrotic and thrombotic protein expression, vascular permeability and microvascular dysfunction, heart inflammatory cell accumulation and activation, and a cytokine storm. Current data indicate that COVID-19 patients with cardiovascular diseases should not discontinue many existing cardiovascular therapies such as ACE inhibitors, angiotensin receptor blockers, steroids, aspirin, statins, and PCSK9 inhibitors. This review aims to furnish a framework relating to COVID-19 and cardiovascular pathophysiology.
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Qamar A, Zhao J, Xu L, McLeod P, Huang X, Jiang J, Liu W, Haig A, Zhang ZX. Cyclophilin D Regulates the Nuclear Translocation of AIF, Cardiac Endothelial Cell Necroptosis and Murine Cardiac Transplant Injury. Int J Mol Sci 2021; 22:11038. [PMID: 34681708 PMCID: PMC8540562 DOI: 10.3390/ijms222011038] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 09/23/2021] [Accepted: 10/08/2021] [Indexed: 12/26/2022] Open
Abstract
Ischemia-reperfusion injury (IRI) is an inevitable consequence of organ transplant procedure and associated with acute and chronic organ rejection in transplantation. IRI leads to various forms of programmed cell death, which worsens tissue damage and accelerates transplant rejection. We recently demonstrated that necroptosis participates in murine cardiac microvascular endothelial cell (MVEC) death and murine cardiac transplant rejection. However, MVEC death under a more complex IRI model has not been studied. In this study, we found that simulating IRI conditions in vitro by hypoxia, reoxygenation and treatment with inflammatory cytokines induced necroptosis in MVECs. Interestingly, the apoptosis-inducing factor (AIF) translocated to the nucleus during MVEC necroptosis, which is regulated by the mitochondrial permeability molecule cyclophilin D (CypD). Furthermore, CypD deficiency in donor cardiac grafts inhibited AIF translocation and mitigated graft IRI and rejection (n = 7; p = 0.002). Our studies indicate that CypD and AIF play significant roles in MVEC necroptosis and cardiac transplant rejection following IRI. Targeting CypD and its downstream AIF may be a plausible approach to inhibit IRI-caused cardiac damage and improve transplant survival.
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Affiliation(s)
- Adnan Qamar
- Matthew Mailing Centre for Translational Transplantation Studies, London Health Sciences Centre, B4-231, 339 Windermere Road, London, ON N6A 5A5, Canada; (A.Q.); (J.Z.); (L.X.); (P.M.); (X.H.); (J.J.)
- Department of Pathology, Western University, 1151 Richmond Street, London, ON N6A 3K7, Canada; (W.L.); (A.H.)
| | - Jianqi Zhao
- Matthew Mailing Centre for Translational Transplantation Studies, London Health Sciences Centre, B4-231, 339 Windermere Road, London, ON N6A 5A5, Canada; (A.Q.); (J.Z.); (L.X.); (P.M.); (X.H.); (J.J.)
- Department of Pathology, Western University, 1151 Richmond Street, London, ON N6A 3K7, Canada; (W.L.); (A.H.)
- Department of Rheumatology and Immunology, The First Hospital of Jilin University, 3808 Jiefang Road, Changchun 130021, China
| | - Laura Xu
- Matthew Mailing Centre for Translational Transplantation Studies, London Health Sciences Centre, B4-231, 339 Windermere Road, London, ON N6A 5A5, Canada; (A.Q.); (J.Z.); (L.X.); (P.M.); (X.H.); (J.J.)
- Department of Pathology, Western University, 1151 Richmond Street, London, ON N6A 3K7, Canada; (W.L.); (A.H.)
| | - Patrick McLeod
- Matthew Mailing Centre for Translational Transplantation Studies, London Health Sciences Centre, B4-231, 339 Windermere Road, London, ON N6A 5A5, Canada; (A.Q.); (J.Z.); (L.X.); (P.M.); (X.H.); (J.J.)
| | - Xuyan Huang
- Matthew Mailing Centre for Translational Transplantation Studies, London Health Sciences Centre, B4-231, 339 Windermere Road, London, ON N6A 5A5, Canada; (A.Q.); (J.Z.); (L.X.); (P.M.); (X.H.); (J.J.)
| | - Jifu Jiang
- Matthew Mailing Centre for Translational Transplantation Studies, London Health Sciences Centre, B4-231, 339 Windermere Road, London, ON N6A 5A5, Canada; (A.Q.); (J.Z.); (L.X.); (P.M.); (X.H.); (J.J.)
| | - Weihua Liu
- Department of Pathology, Western University, 1151 Richmond Street, London, ON N6A 3K7, Canada; (W.L.); (A.H.)
| | - Aaron Haig
- Department of Pathology, Western University, 1151 Richmond Street, London, ON N6A 3K7, Canada; (W.L.); (A.H.)
| | - Zhu-Xu Zhang
- Matthew Mailing Centre for Translational Transplantation Studies, London Health Sciences Centre, B4-231, 339 Windermere Road, London, ON N6A 5A5, Canada; (A.Q.); (J.Z.); (L.X.); (P.M.); (X.H.); (J.J.)
- Department of Pathology, Western University, 1151 Richmond Street, London, ON N6A 3K7, Canada; (W.L.); (A.H.)
- Multi-Organ Transplant Program, London Health Sciences Centre, London, ON N6A 5A5, Canada
- Division of Nephrology, Department of Medicine, Western University, London, ON N6A 3K7, Canada
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Galenkamp KMO, Commisso C. The Golgi as a "Proton Sink" in Cancer. Front Cell Dev Biol 2021; 9:664295. [PMID: 34055797 PMCID: PMC8155353 DOI: 10.3389/fcell.2021.664295] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 04/21/2021] [Indexed: 12/19/2022] Open
Abstract
Cancer cells exhibit increased glycolytic flux and adenosine triphosphate (ATP) hydrolysis. These processes increase the acidic burden on the cells through the production of lactate and protons. Nonetheless, cancer cells can maintain an alkaline intracellular pH (pHi) relative to untransformed cells, which sets the stage for optimal functioning of glycolytic enzymes, evasion of cell death, and increased proliferation and motility. Upregulation of plasma membrane transporters allows for H+ and lactate efflux; however, recent evidence suggests that the acidification of organelles can contribute to maintenance of an alkaline cytosol in cancer cells by siphoning off protons, thereby supporting tumor growth. The Golgi is such an acidic organelle, with resting pH ranging from 6.0 to 6.7. Here, we posit that the Golgi represents a "proton sink" in cancer and delineate the proton channels involved in Golgi acidification and the ion channels that influence this process. Furthermore, we discuss ion channel regulators that can affect Golgi pH and Golgi-dependent processes that may contribute to pHi homeostasis in cancer.
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Affiliation(s)
- Koen M. O. Galenkamp
- Cell and Molecular Biology of Cancer Program, NCI-Designated Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, United States
| | - Cosimo Commisso
- Cell and Molecular Biology of Cancer Program, NCI-Designated Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, United States
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Roberts KA, Colley L, Agbaedeng TA, Ellison-Hughes GM, Ross MD. Vascular Manifestations of COVID-19 - Thromboembolism and Microvascular Dysfunction. Front Cardiovasc Med 2020; 7:598400. [PMID: 33195487 PMCID: PMC7649150 DOI: 10.3389/fcvm.2020.598400] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 09/28/2020] [Indexed: 12/15/2022] Open
Abstract
The coronavirus pandemic has reportedly infected over 31.5 million individuals and caused over 970,000 deaths worldwide (as of 22nd Sept 2020). This novel coronavirus, officially named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), although primarily causes significant respiratory distress, can have significant deleterious effects on the cardiovascular system. Severe cases of the virus frequently result in respiratory distress requiring mechanical ventilation, often seen, but not confined to, individuals with pre-existing hypertension and cardiovascular disease, potentially due to the fact that the virus can enter the circulation via the lung alveoli. Here the virus can directly infect vascular tissues, via TMPRSS2 spike glycoprotein priming, thereby facilitating ACE-2-mediated viral entry. Clinical manifestations, such as vasculitis, have been detected in a number of vascular beds (e.g., lungs, heart, and kidneys), with thromboembolism being observed in patients suffering from severe coronavirus disease (COVID-19), suggesting the virus perturbs the vasculature, leading to vascular dysfunction. Activation of endothelial cells via the immune-mediated inflammatory response and viral infection of either endothelial cells or cells involved in endothelial homeostasis, are some of the multifaceted mechanisms potentially involved in the pathogenesis of vascular dysfunction within COVID-19 patients. In this review, we examine the evidence of vascular manifestations of SARS-CoV-2, the potential mechanism(s) of entry into vascular tissue and the contribution of endothelial cell dysfunction and cellular crosstalk in this vascular tropism of SARS-CoV-2. Moreover, we discuss the current evidence on hypercoagulability and how it relates to increased microvascular thromboembolic complications in COVID-19.
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Affiliation(s)
- Kirsty A. Roberts
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Liam Colley
- School of Sport, Health & Exercise Science, Bangor University, Bangor, United Kingdom
| | - Thomas A. Agbaedeng
- Centre for Heart Rhythm Disorders, School of Medicine, The University of Adelaide, Adelaide, SA, Australia
| | - Georgina M. Ellison-Hughes
- Centre for Human and Physiological Sciences, Faculty of Life Sciences & Medicine, School of Basic and Medical Biosciences, King's College London, London, United Kingdom
| | - Mark D. Ross
- School of Applied Sciences, Edinburgh Napier University, Edinburgh, United Kingdom
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6
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Schneider MF, Fallah MA, Mess C, Obser T, Schneppenheim R, Alexander-Katz A, Schneider SW, Huck V. Platelet adhesion and aggregate formation controlled by immobilised and soluble VWF. BMC Mol Cell Biol 2020; 21:64. [PMID: 32917131 PMCID: PMC7488753 DOI: 10.1186/s12860-020-00309-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Accepted: 08/26/2020] [Indexed: 11/21/2022] Open
Abstract
Background It has been demonstrated that von Willebrand factor (VWF) mediated platelet-endothelium and platelet-platelet interactions are shear dependent. The VWF’s mobility under dynamic conditions (e.g. flow) is pivotal to platelet adhesion and VWF-mediated aggregate formation in the cascade of VWF-platelet interactions in haemostasis. Results Combining microfluidic tools with fluorescence and reflection interference contrast microscopy (RICM), here we show, that specific deletions in the A-domains of the biopolymer VWF affect both, adhesion and aggregation properties independently. Intuitively, the deletion of the A1-domain led to a significant decrease in both adhesion and aggregate formation of platelets. Nevertheless, the deletion of the A2-domain revealed a completely different picture, with a significant increase in formation of rolling aggregates (gain of function). We predict that the A2-domain effectively ‘masks’ the potential between the platelet glycoprotein (GP) Ib and the VWF A1-domain. Furthermore, the deletion of the A3-domain led to no significant variation in either of the two functional characteristics. Conclusions These data demonstrate that the macroscopic functional properties i.e. adhesion and aggregate formation cannot simply be assigned to the properties of one particular domain, but have to be explained by cooperative phenomena. The absence or presence of molecular entities likewise affects the properties (thermodynamic phenomenology) of its neighbours, therefore altering the macromolecular function.
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Affiliation(s)
- Matthias F Schneider
- Department of Physics, Medical and Biological Physics, Technical University Dortmund, Emil-Figge-Str. 50, 44227, Dortmund, Germany
| | - Mohammad A Fallah
- Department of Chemistry, University of Konstanz, Universitätsstr. 10, 78457, Constance, Germany
| | - Christian Mess
- University Medical Centre Hamburg-Eppendorf, Centre for Internal Medicine, Martinistr. 52, 20246, Hamburg, Germany
| | - Tobias Obser
- Department of Paediatric Haematology and Oncology, University Medical Centre Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Reinhard Schneppenheim
- Department of Paediatric Haematology and Oncology, University Medical Centre Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Alfredo Alexander-Katz
- Department of Materials Science and Engineerin, Massachusetts Institute of Technology, 400 Technology Sq. (NE46-605), Cambridge, MA, 02139, USA
| | - Stefan W Schneider
- University Medical Centre Hamburg-Eppendorf, Centre for Internal Medicine, Martinistr. 52, 20246, Hamburg, Germany
| | - Volker Huck
- University Medical Centre Hamburg-Eppendorf, Centre for Internal Medicine, Martinistr. 52, 20246, Hamburg, Germany. .,Heidelberg University, Medical Faculty Mannheim, Experimental Dermatology, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany.
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Cure E, Cure MC. COVID-19 May Predispose to Thrombosis by Affecting Both Vascular Endothelium and Platelets. CLINICAL AND APPLIED THROMBOSIS/HEMOSTASIS : OFFICIAL JOURNAL OF THE INTERNATIONAL ACADEMY OF CLINICAL AND APPLIED THROMBOSIS/HEMOSTASIS 2020. [PMID: 32619104 DOI: 10.1177/1076029620933945.] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Erkan Cure
- Department of Internal Medicine, Ota Jinemed Hospital, Istanbul, Turkey
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Cure E, Cure MC. COVID-19 May Predispose to Thrombosis by Affecting Both Vascular Endothelium and Platelets. Clin Appl Thromb Hemost 2020; 26:1076029620933945. [PMID: 32619104 PMCID: PMC7495934 DOI: 10.1177/1076029620933945] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Affiliation(s)
- Erkan Cure
- Department of Internal Medicine, Ota Jinemed Hospital, Istanbul, Turkey
- Erkan Cure, Department of Internal Medicine, Ota Jinemed Hospital, Muradiye Mahallesi Nuzhetiye Cad, Deryadil Sokagi No: 1, 34357 Besiktas, Istanbul, Turkey.
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Khatami M. Cancer; an induced disease of twentieth century! Induction of tolerance, increased entropy and 'Dark Energy': loss of biorhythms (Anabolism v. Catabolism). Clin Transl Med 2018; 7:20. [PMID: 29961900 PMCID: PMC6026585 DOI: 10.1186/s40169-018-0193-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2018] [Accepted: 05/29/2018] [Indexed: 12/15/2022] Open
Abstract
Maintenance of health involves a synchronized network of catabolic and anabolic signals among organs/tissues/cells that requires differential bioenergetics from mitochondria and glycolysis (biological laws or biorhythms). We defined biological circadian rhythms as Yin (tumoricidal) and Yang (tumorigenic) arms of acute inflammation (effective immunity) involving immune and non-immune systems. Role of pathogens in altering immunity and inducing diseases and cancer has been documented for over a century. However, in 1955s decision makers in cancer/medical establishment allowed public (current baby boomers) to consume million doses of virus-contaminated polio vaccines. The risk of cancer incidence and mortality sharply rose from 5% (rate of hereditary/genetic or innate disease) in 1900s, to its current scary status of 33% or 50% among women and men, respectively. Despite better hygiene, modern detection technologies and discovery of antibiotics, baby boomers and subsequent 2–3 generations are sicker than previous generations at same age. American health status ranks last among other developed nations while America invests highest amount of resources for healthcare. In this perspective we present evidence that cancer is an induced disease of twentieth century, facilitated by a great deception of cancer/medical establishment for huge corporate profits. Unlike popularized opinions that cancer is 100, 200 or 1000 diseases, we demonstrate that cancer is only one disease; the severe disturbances in biorhythms (differential bioenergetics) or loss of balance in Yin and Yang of effective immunity. Cancer projects that are promoted and funded by decision makers are reductionist approaches, wrong and unethical and resulted in loss of millions of precious lives and financial toxicity to society. Public vaccination with pathogen-specific vaccines (e.g., flu, hepatitis, HPV, meningitis, measles) weakens, not promotes, immunity. Results of irresponsible projects on cancer sciences or vaccines are increased population of drug-dependent sick society. Outcome failure rates of claimed ‘targeted’ drugs, ‘precision’ or ‘personalized’ medicine are 90% (± 5) for solid tumors. We demonstrate that aging, frequent exposures to environmental hazards, infections and pathogen-specific vaccines and ingredients are ‘antigen overload’ for immune system, skewing the Yin and Yang response profiles and leading to induction of ‘mild’, ‘moderate’ or ‘severe’ immune disorders. Induction of decoy or pattern recognition receptors (e.g., PRRs), such as IRAK-M or IL-1dRs (‘designer’ molecules) and associated genomic instability and over-expression of growth promoting factors (e.g., pyruvate kinases, mTOR and PI3Ks, histamine, PGE2, VEGF) could lead to immune tolerance, facilitating cancer cells to hijack anabolic machinery of immunity (Yang) for their increased growth requirements. Expression of constituent embryonic factors would negatively regulate differentiation of tumor cells through epithelial–mesenchymal-transition and create “dual negative feedback loop” that influence tissue metabolism under hypoxic conditions. It is further hypothesized that induction of tolerance creates ‘dark energy’ and increased entropy and temperature in cancer microenvironment allowing disorderly cancer proliferation and mitosis along with increased glucose metabolism via Crabtree and Pasteur Effects, under mitophagy and ribophagy, conditions that are toxic to host survival. Effective translational medicine into treatment requires systematic and logical studies of complex interactions of tumor cells with host environment that dictate clinical outcomes. Promoting effective immunity (biological circadian rhythms) are fundamental steps in correcting host differential bioenergetics and controlling cancer growth, preventing or delaying onset of diseases and maintaining public health. The author urges independent professionals and policy makers to take a closer look at cancer dilemma and stop the ‘scientific/medical ponzi schemes’ of a powerful group that control a drug-dependent sick society before all hopes for promoting public health evaporate.
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Affiliation(s)
- Mahin Khatami
- Inflammation, Aging and Cancer, National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD, USA.
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Intracellular acidification reduces l-arginine transport via system y+L but not via system y+/CATs and nitric oxide synthase activity in human umbilical vein endothelial cells. Biochim Biophys Acta Mol Basis Dis 2018; 1864:1192-1202. [DOI: 10.1016/j.bbadis.2018.01.032] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 01/15/2018] [Accepted: 01/31/2018] [Indexed: 12/13/2022]
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Celis N, Araos J, Sanhueza C, Toledo F, Beltrán AR, Pardo F, Leiva A, Ramírez MA, Sobrevia L. Intracellular acidification increases adenosine transport in human umbilical vein endothelial cells. Placenta 2017; 51:10-17. [DOI: 10.1016/j.placenta.2017.01.120] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 01/01/2017] [Accepted: 01/14/2017] [Indexed: 12/16/2022]
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Khatami M. Is cancer a severe delayed hypersensitivity reaction and histamine a blueprint? Clin Transl Med 2016; 5:35. [PMID: 27558401 PMCID: PMC4996813 DOI: 10.1186/s40169-016-0108-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2016] [Accepted: 07/04/2016] [Indexed: 02/08/2023] Open
Abstract
Longevity and accumulation of multiple context-dependent signaling pathways of long-standing inflammation (antigen-load or oxidative stress) are the results of decreased/altered regulation of immunity and loss of control switch mechanisms that we defined as Yin and Yang of acute inflammation or immune surveillance. Chronic inflammation is initiated by immune disruptors-induced progressive changes in physiology and function of susceptible host tissues that lead to increased immune suppression and multistep disease processes including carcinogenesis. The interrelated multiple hypotheses that are presented for the first time in this article are extension of author's earlier series of 'accidental' discoveries on the role of inflammation in developmental stages of immune dysfunction toward tumorigenesis and angiogenesis. Detailed analyses of data on chronic diseases suggest that nearly all age-associated illnesses, generally categorized as 'mild' (e.g., increased allergies), 'moderate' (e.g., hypertension, colitis, gastritis, pancreatitis, emphysema) or 'severe' (e.g., accelerated neurodegenerative and autoimmune diseases or site-specific cancers and metastasis) are variations of hypersensitivity responses of tissues that are manifested as different diseases in immune-responsive or immune-privileged tissues. Continuous release/presence of low level histamine (subclinical) in circulation could contribute to sustained oxidative stress and induction of 'mild' or 'moderate' or 'severe' (immune tsunami) immune disorders in susceptible tissues. Site-specific cancers are proposed to be 'severe' (irreversible) forms of cumulative delayed hypersensitivity responses that would induce immunological chaos in favor of tissue growth in target tissues. Shared or special features of growth from fetus development into adulthood and aging processes and carcinogenesis are briefly compared with regard to energy requirements of highly complex function of Yin and Yang. Features of Yang (growth-promoting) arm of acute inflammation during fetus and cancer growth will be compared for consuming low energy from glycolysis (Warburg effect). Growth of fetus and cancer cells under hypoxic conditions and impaired mitochondrial energy requirements of tissues including metabolism of essential branched amino acids (e.g., val, leu, isoleu) will be compared for proposing a working model for future systematic research on cancer biology, prevention and therapy. Presentation of a working model provides insightful clues into bioenergetics that are required for fetus growth (absence of external threat and lack of high energy-demands of Yin events and parasite-like survival in host), normal growth in adulthood (balance in Yin and Yang processes) or disease processes and carcinogenesis (loss of balance in Yin-Yang). Future studies require focusing on dynamics and promotion of natural/inherent balance between Yin (tumoricidal) and Yang (tumorigenic) of effective immunity that develop after birth. Lawless growth of cancerous cells and loss of cell contact inhibition could partially be due to impaired mitochondria (mitophagy) that influence metabolism of branched chain amino acids for biosynthesis of structural proteins. The author invites interested scientists with diverse expertise to provide comments, confirm, dispute and question and/or expand and collaborate on many components of the proposed working model with the goal to better understand cancer biology for future designs of cost-effective research and clinical trials and prevention of cancer. Initial events during oxidative stress-induced damages to DNA/RNA repair mechanisms and inappropriate expression of inflammatory mediators are potentially correctable, preventable or druggable, if future studies were to focus on systematic understanding of early altered immune response dynamics toward multistep chronic diseases and carcinogenesis.
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Affiliation(s)
- Mahin Khatami
- National Cancer Institute (NCI), the National Institutes of Health (NIH), Bethesda, MD, USA.
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Araos J, Silva L, Salsoso R, Sáez T, Barros E, Toledo F, Gutiérrez J, Pardo F, Leiva A, Sanhueza C, Sobrevia L. Intracellular and extracellular pH dynamics in the human placenta from diabetes mellitus. Placenta 2016; 43:47-53. [DOI: 10.1016/j.placenta.2016.05.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 05/03/2016] [Accepted: 05/07/2016] [Indexed: 10/21/2022]
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Abstract
Background: Diabetes aggravates brain injury after cerebral ischemia/reperfusion (I/R). Objective: To investigate whether limb I/R causes cerebral injury in a rat diabetes model and whether glycogen synthase kinase-3β (GSK-3β) is involved. Methods: Male adult Sprague-Dawley rats were assigned into streptozotocin-induced diabetes (n = 30; blood glucose ≥16.7 mmol/L) or control (n = 20) groups, further subdivided into diabetes I/R (3-hour femoral artery/vein clamping), diabetes-I/R + TDZD-8 (I/R plus GSK-3β inhibitor), diabetes-sham, control-sham and control-I/R groups (n = 10 each). Cortical and hippocampal morphology (hematoxylin/eosin); hippocampal CA1 apoptosis (TUNEL assay); cleaved caspase-3 (apoptosis), and Iba1 (microglial activation) protein expression (immunohistochemistry); phosphorylated/total GSK-3β and nuclear factor-κB (NF-κB) protein levels (Western blotting); and serum and brain tissue tumor necrosis factor (TNF)-α levels (enzyme-linked immunosorbent assay) were analyzed. Results: The diabetes-I/R group showed greater cortical and hippocampal injury, apoptosis, cleaved caspase-3 expression and Iba1 expression than the control-I/R group; TDZD-8 reduced injury/apoptosis and cleaved caspase-3/Iba1 expressions. The diabetes-I/R group had lower p-GSK-3β and p-NF-κBp65 expression than the control-I/R group (P < 0.05); TDZD-8 increased p-GSK-3β expression but decreased p-NF-κBp65 expression (P < 0.05). The diabetes-I/R group showed higher elevation of serum and brain tissue TNF-α than the control-I/R group (P < 0.05); TDZD-8 reduced TNF-α production. Conclusions: Diabetes exacerbates limb I/R-induced cerebral damage and activates NF-κB and GSK-3β.
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Yang J, Zhao JX, Wang Y, Chen G, Cheng WN, Luo X, Pei XT, Zhao L, Su Q, Zhou H. Effects of sodium pyruvate on ameliorating metabolic acidosis. ARTIFICIAL CELLS NANOMEDICINE AND BIOTECHNOLOGY 2014; 44:48-55. [PMID: 24697727 DOI: 10.3109/21691401.2014.901335] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE To examine the effects of sodium pyruvate (SP) on metabolic acidosis. METHODS For the in vivo experiments, we evaluated effects of SP on an ammonium chloride (NH4Cl)-induced hyperchloremic acidosis rat model. SP was infused at overall doses of 2, 4, and 6 mmol·kg(- 1) for the SP1, SP2, and SP3 groups, respectively. Treatment with sodium bicarbonate (SB) was used as a positive control (2 mmol·kg(- 1)), and treatment with normal saline (NS) was used as a volume control (2 mL·kg(- 1)). Blood was sampled from the ophthalmic venous plexus for pH, blood gases, electrolytes, glucose, creatinine (Cr), and urea analysis after injection. For the in vitro experiment, propionate was applied to induce intracellular acidosis in human endothelial cells. Intracellular pH (pHi) was fluorimetrically measured after the addition of SP. RESULTS In the in vivo study, the pH of SP1 group showed no significant difference compared with that of the NS group. The SP2 and SP3 groups had a higher pH than the NS group (P < 0.01). The SP3 group had a higher pH than the SB group (P < 0.05) and SP1 group (P < 0.05). Moreover, SP treatment ameliorated the abnormality of calcium and decreased the blood potassium levels. The SP3 group had higher glucose levels than SP1 group (P < 0.05). No significant differences were observed between all the groups in the plasma Cr and urea levels. In the in vitro study, the pHi increased immediately after the addition of SP. CONCLUSION The data suggest that intravascular treatment with SP represents a novel therapeutic strategy to ameliorate metabolic acidosis.
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Affiliation(s)
- Jing Yang
- a Institute of Transfusion Medicine, Academy of Military Medical Sciences , Beijing , P.R. China
| | - Jing-Xiang Zhao
- a Institute of Transfusion Medicine, Academy of Military Medical Sciences , Beijing , P.R. China
| | - Ying Wang
- a Institute of Transfusion Medicine, Academy of Military Medical Sciences , Beijing , P.R. China
| | - Gan Chen
- a Institute of Transfusion Medicine, Academy of Military Medical Sciences , Beijing , P.R. China
| | - Wei-Na Cheng
- b Department of Biological Engineering , College of Environment and Chemical Engineering, Yanshan University , Qinhuangdao , P. R. China
| | - Xin Luo
- a Institute of Transfusion Medicine, Academy of Military Medical Sciences , Beijing , P.R. China
| | - Xue-Tao Pei
- a Institute of Transfusion Medicine, Academy of Military Medical Sciences , Beijing , P.R. China
| | - Lian Zhao
- a Institute of Transfusion Medicine, Academy of Military Medical Sciences , Beijing , P.R. China
| | - Qin Su
- c The First Affiliated Hospital of General Hospital of PLA , Beijing , P. R. China
| | - Hong Zhou
- a Institute of Transfusion Medicine, Academy of Military Medical Sciences , Beijing , P.R. China
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Huck V, Schneider MF, Gorzelanny C, Schneider SW. The various states of von Willebrand factor and their function in physiology and pathophysiology. Thromb Haemost 2014; 111:598-609. [PMID: 24573248 DOI: 10.1160/th13-09-0800] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Accepted: 02/08/2014] [Indexed: 11/05/2022]
Abstract
The specific interactions of von Willebrand factor (VWF) with the vessel wall, platelets or other interfaces strongly depend on (a shear-induced) VWF activation. Shear flow has been shown to induce a conformational transition of VWF, but is modulated by its thermodynamic state (state-function relationship). The state in turn is determined by physical (e.g. vessel geometry), physico-chemical (e.g. pH) and molecular-biological (e.g. mutants, binding) factors. Combining established results with recent insights, we reconstruct VWF biology and its state-function relationship from endothelial cell release to final degradation in the human vasculature. After VWF secretion, endothelial-anchored and shear activated VWF multimers can rapidly interact with surrounding colloids, typically with platelets. Simultaneously, this VWF activation enables ADAMTS13 to cleave VWF multimers thereby limiting VWF binding capacity. The subsequent cell-surface dissociation leads to a VWF recoiling to a globular conformation, shielding from further degradation by ADAMTS13. High local concentrations of these soluble VWF multimers, transported to the downstream vasculature, are capable for an immediate reactivation and re-polymerisation initiating colloid-binding or VWF-colloid aggregation at the site of inflamed endothelium, vessel injuries or pathological high-shear areas. Focusing on these functional steps in the lifecycle of VWF, its qualitative and quantitative deficiencies in the different VWD types will facilitate more precise diagnostics and reliable risk stratification for prophylactic therapies. The underlying biophysical principles are of general character, which broadens prospective studies on the physiological and pathophysiological impact of VWF and VWF-associated diseases and beares hope for a more universal understanding of an entire class of phenomena.
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Affiliation(s)
| | - Matthias F Schneider
- Prof. Dr. Matthias F. Schneider, Biological Physics Group, Boston University, Department of Mechanical Engineering, 110 Cummington Street, Boston, MA 02215, USA, Tel.: +1 617 353 3951, Fax: +1 617 353 3951, E-mail:
| | | | - Stefan W Schneider
- Prof. Dr. Stefan W. Schneider, Department of Dermatology, Experimental Dermatology, Heidelberg University, Medical Faculty Mannheim, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany, Tel: +49 621 383 6901, Fax:+49 621 383 6903, E-mail:
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17
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Blechinger J, Bauer AT, Torrano AA, Gorzelanny C, Bräuchle C, Schneider SW. Uptake kinetics and nanotoxicity of silica nanoparticles are cell type dependent. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2013; 9:3970-80, 3906. [PMID: 23681841 DOI: 10.1002/smll.201301004] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2013] [Indexed: 05/22/2023]
Abstract
In this study, it is shown that the cytotoxic response of cells as well as the uptake kinetics of nanoparticles (NPs) is cell type dependent. We use silica NPs with a diameter of 310 nm labeled with perylene dye and 304 nm unlabeled particles to evaluate cell type-dependent uptake and cytotoxicity on human vascular endothelial cells (HUVEC) and cancer cells derived from the cervix carcinoma (HeLa). Besides their size, the particles are characterized concerning homogeneity of the labeling and their zeta potential. The cellular uptake of the labeled NPs is quantified by imaging the cells via confocal microscopy in a time-dependent manner, with subsequent image analysis via a custom-made and freely available digital method, Particle_in_Cell-3D. We find that within the first 4 h of interaction, the uptake of silica NPs into the cytoplasm is up to 10 times more efficient in HUVEC than in HeLa cells. Interestingly, after 10 or 24 h of interaction, the number of intracellular particles for HeLa cells by far surpasses the one for HUVEC. Inhibitor studies show that these endothelial cells internalize 310 nm SiO₂ NPs via the clathrin-dependent pathway. Remarkably, the differences in the amount of taken up NPs are not directly reflected by the metabolic activity and membrane integrity of the individual cell types. Interaction with NPs leads to a concentration-dependent decrease in mitochondrial activity and an increase in membrane leakage for HUVEC, whereas HeLa cells show only a reduced mitochondrial activity and no membrane leakage. In addition, silica NPs lead to HUVEC cell death while HeLa cells survive. These findings indicate that HUVEC are more sensitive than HeLa cells upon silica NP exposure.
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Affiliation(s)
- Julia Blechinger
- Ludwig-Maximilians-University Munich, Department of Chemistry and Center for NanoScience, Butenandtstr.11, Gerhard-Ertl-Gebäude, 81377 Munich, Germany
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18
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Cytotoxicity of silica nanoparticles through exocytosis of von Willebrand factor and necrotic cell death in primary human endothelial cells. Biomaterials 2011; 32:8385-93. [PMID: 21840590 DOI: 10.1016/j.biomaterials.2011.07.078] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Accepted: 07/26/2011] [Indexed: 11/22/2022]
Abstract
Nanoparticle-induced endothelial cell (EC) dysfunction, due to the induction of inflammation and/or the activation of the coagulation system, is associated with pulmonary and ischemic cardiovascular diseases. Although it is contigent on several mechanisms, involving formation of reactive oxygen species and inflammatory cytokines such as interleukin (IL)-6 and 8, the involvement of the coagulation system is not well understood. The results of toxicity assays using the tetrazolium reduction (MTT) and lactate dehydrogenase (LDH) release showed that silica NP-induced cytotoxicity depends on the size and the dose of applied NP. Moreover, propidium iodide (PI) stainings and caspase 3/7 assays identified increased necrosis in ECs. Exposing human umbilical vein endothelial cells (HUVECs) to SiO(2) NP with diameters of 304 nm and 310 nm led to significant increase of Weibel-Palade body (WPB) exocytosis, associated with the release of von Willebrand factor (VWF) and the formation of ultralarge fibers (ULVWF). High resolution microscopy techniques revealed that internalization and perinuclear localization of perylene-labeled NP with a size of 310 nm affect not only viability, but also cell migration and proliferation. In conclusion, our data indicate that NP-induced activation and dysfunction of ECs is reflected by release of VWF and necrotic cell death.
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19
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Crimi E, Taccone FS, Infante T, Scolletta S, Crudele V, Napoli C. Effects of intracellular acidosis on endothelial function: an overview. J Crit Care 2011; 27:108-18. [PMID: 21798701 DOI: 10.1016/j.jcrc.2011.06.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2011] [Revised: 05/17/2011] [Accepted: 06/03/2011] [Indexed: 01/13/2023]
Abstract
The endothelium represents the largest functional organ in the human body playing an active role in vasoregulation, coagulation, inflammation, and microvascular permeability. Endothelium contributes to maintain vascular integrity, intravascular volume, and tissue oxygenation promoting inflammatory network response for local defense and repair. Acid-basis homeostasis is an important physiologic parameter that controls cell function, and changes in pH can influence vascular tone by regulating endothelium and vascular smooth muscle cells. This review presents a current perspective of the effects of intracellular acidosis on the function and the basic regulatory mechanisms of endothelial cells.
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Affiliation(s)
- Ettore Crimi
- Department of Anesthesia and Critical Care Medicine, Shands Hospital, University of Florida, Gainesville, FL 32608, USA
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20
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Brenninkmeijer L, Kuehl C, Geldart AM, Arons E, Christou H. Heme oxygenase-1 does not mediate the effects of extracellular acidosis on vascular smooth muscle cell proliferation, migration, and susceptibility to apoptosis. J Vasc Res 2011; 48:285-96. [PMID: 21273783 DOI: 10.1159/000321555] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2010] [Accepted: 09/17/2010] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Unbalanced vascular smooth muscle cell (VSMC) proliferation, migration, and apoptosis contribute to vascular disorders such as atherosclerosis, restenosis, and pulmonary hypertension. The effect of extracellular acidosis (EA) on VSMC homeostasis is incompletely understood but we previously reported that EA increases heme oxygenase-1 (HO-1) expression in VSMCs. Since HO-1 regulates VSMC proliferation and apoptosis we sought to define the role of HO-1 in VSMC responses to EA. METHODS Mouse aortic smooth muscle cells (MASMCs) were isolated from wild-type and HO-1-null mice. Cell proliferation and migration assays were done in a physiologic pH (7.4) or EA (pH 6.8). VSMC apoptosis in response to hydrogen peroxide was assessed by JC-1 staining, caspase-3 cleavage, annexin V, and Hoechst staining. RESULTS Wild-type MASMCs showed decreased proliferation and migration at pH 6.8 compared to pH 7.4. This observation was also true in HO-1-null MASMCs. Although wild-type and HO-1-null cells showed differences in the mode and kinetics of cell death, both genotypes exhibited increased susceptibility to hydrogen peroxide-induced apoptosis at pH 6.8 compared to 7.4. CONCLUSIONS EA inhibits VSMC proliferation and migration and increases susceptibility to oxidant-induced apoptosis. These effects of acidosis on VSMC homeostasis are independent of HO-1.
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Affiliation(s)
- Lineke Brenninkmeijer
- Division of Newborn Medicine, Brigham and Women's and Children's Hospitals and Harvard Medical School, Boston, MA 02215, USA
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21
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Control of MCT1 function in cerebrovascular endothelial cells by intracellular pH. Brain Res 2010; 1376:10-22. [PMID: 21192921 DOI: 10.1016/j.brainres.2010.12.060] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2010] [Revised: 12/08/2010] [Accepted: 12/20/2010] [Indexed: 02/03/2023]
Abstract
Monocarboxylic Acid Transporter 1 (MCT1) is expressed on the plasma membrane of cerebrovascular endothelial cells where it is the only known facilitator of lactic acid transport across the blood brain barrier. During stroke, brain injury, and certain other brain pathologies, anaerobic glycolysis produces severe lactic acidosis of brain tissue leading to brain cell damage. Therefore, a better understanding of factors that control MCT1 function may be the key to better understanding the origins and treatment of pathological lactic acidosis. In this study, we characterized the effects of intracellular pH in controlling MCT1 function and showed that microtubule disruption targeted this mechanism in rat cerebrovascular endothelial cells. Acidic intracellular pH values were shown to strongly inhibit lactic acid transport into the cytoplasmic space, while alkalinization of the cytoplasm significantly enhanced this transport function. These results support a better understanding of how cerebrovascular endothelial MCT1 may contribute to the development of lactic acidosis in brain pathologies, and suggest targeting it as a novel therapy.
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22
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Luca MC, Liuni A, DiFabio J, Gori T, Parker JD. The acute administration of either amiloride or captopril does not prevent endothelial dysfunction induced by ischemia and reperfusion in the human forearm vasculature. Can J Physiol Pharmacol 2010; 88:996-1001. [DOI: 10.1139/y10-081] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Animal studies have demonstrated the ability of both sodium–hydrogen exchange inhibitors and angiotensin-converting enzyme inhibitors to reduce infarct size and preserve postischemic ventricular function following ischemia and reperfusion (IR) injury. Whether these interventions can also prevent IR-induced impairment of endothelial function in humans has not been investigated. We performed 2 separate double-blind, placebo-controlled, crossover studies. In the first study, 10 healthy volunteers were randomized to receive oral amiloride (10 mg) or a placebo. In a separate study, another group of volunteers (n = 10) was randomized to receive oral captopril (50 mg) or a placebo. At the time of the peak hemodynamic effect of the drug (3 and 1.5 h after administration of amiloride and captopril, respectively), endothelium-dependent, flow-mediated dilatation of the radial artery was measured before and after IR. IR significantly blunted flow-mediated dilatation in all groups (placebo: pre-IR: 6.8% ± 0.7%; post-IR: 2.9% ± 0.9%; P < 0.01; amiloride: pre-IR: 5.9% ± 0.6%; post-IR: 2.1% ± 1.3%; P = 0.01; captopril: pre-IR: 6.0% ± 0.5%; post-IR: 2.0% ± 0.6%; P < 0.01). In humans, neither 10 mg of oral amiloride nor 50 mg of oral captopril was able to provide protection against IR-induced endothelial dysfunction in the peripheral vasculature.
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Affiliation(s)
- Mary Clare Luca
- Mount Sinai Hospital, Division of Cardiology, 600 University Avenue, Toronto, ON M5G 1X5, Canada; Department of Pharmacology and Toxicology, University of Toronto, 1 King’s College Circle, Toronto, ON M5S 1A8, Canada
- University Medical Centre of Mainz, Langenbeckstrasse 1, 55131 Mainz, Germany
| | - Andrew Liuni
- Mount Sinai Hospital, Division of Cardiology, 600 University Avenue, Toronto, ON M5G 1X5, Canada; Department of Pharmacology and Toxicology, University of Toronto, 1 King’s College Circle, Toronto, ON M5S 1A8, Canada
- University Medical Centre of Mainz, Langenbeckstrasse 1, 55131 Mainz, Germany
| | - Jonathan DiFabio
- Mount Sinai Hospital, Division of Cardiology, 600 University Avenue, Toronto, ON M5G 1X5, Canada; Department of Pharmacology and Toxicology, University of Toronto, 1 King’s College Circle, Toronto, ON M5S 1A8, Canada
- University Medical Centre of Mainz, Langenbeckstrasse 1, 55131 Mainz, Germany
| | - Tommaso Gori
- Mount Sinai Hospital, Division of Cardiology, 600 University Avenue, Toronto, ON M5G 1X5, Canada; Department of Pharmacology and Toxicology, University of Toronto, 1 King’s College Circle, Toronto, ON M5S 1A8, Canada
- University Medical Centre of Mainz, Langenbeckstrasse 1, 55131 Mainz, Germany
| | - John D. Parker
- Mount Sinai Hospital, Division of Cardiology, 600 University Avenue, Toronto, ON M5G 1X5, Canada; Department of Pharmacology and Toxicology, University of Toronto, 1 King’s College Circle, Toronto, ON M5S 1A8, Canada
- University Medical Centre of Mainz, Langenbeckstrasse 1, 55131 Mainz, Germany
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23
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The mechanism of melanoma-associated thrombin activity and von Willebrand factor release from endothelial cells. J Invest Dermatol 2010; 130:2259-68. [PMID: 20505748 DOI: 10.1038/jid.2010.136] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Activation of the coagulation system in malignancy enables tumor spreading and is thus associated with poor prognosis for the patient. In this study, we analyzed the in vitro mechanisms by which two human metastatic melanoma cell lines, MV3 and WM9, transform the vascular endothelium into a prothrombotic activated state. We show that both melanoma cell lines activate prothrombin due to tissue factor (TF) expression by showing that thrombin generation was blocked with a TF-neutralizing antibody and TF-siRNA. In addition, using the cysteine protease inhibitor E-64, we excluded the formerly described cancer procoagulant (CP) as a major factor contributing to thrombin generation. Furthermore, we describe a direct thrombin-independent response of endothelial cells (ECs) to MV3-derived supernatant as measured by rapid release of VWF. We also show that two clinically approved LMWHs, tinzaparin and enoxaparin, are effective inhibitors of thrombin generation and thrombin activity in plasma. Furthermore, our data indicate a protective effect of heparins on EC activation as shown by reduced VWF release in response to MV3 supernatant. These promising effects of heparins on the melanoma-induced thrombotic conditions justify further clinical investigations in the field of oncology.
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Antonova OA, Loktionova SA, Romanov YA, Shustova ON, Khachikian MV, Mazurov AV. Activation and damage of endothelial cells upon hypoxia/reoxygenation. Effect of extracellular pH. BIOCHEMISTRY (MOSCOW) 2009; 74:605-12. [PMID: 19645664 DOI: 10.1134/s0006297909060030] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Disturbances of blood flow upon vascular occlusions and spasms result in hypoxia and acidosis, while its subsequent restoration leads to reoxygenation and pH normalization (re-alkalization) in ischemic sites of the vascular bed. The effect of hypoxia/reoxygenation on activation and stimulation of apoptosis in cultured human endothelial cells was studied. The cells were subjected to hypoxia (2% O2, 5% CO2, 93% N(2)) for 24 h followed by reoxygenation (21% O2, 5% CO2, 74% N(2)) for 5 h. Reoxygenation was carried out at different pH-6.4 (preservation of acidosis after hypoxia), 7.0, and 7.4 (partial and complete re-alkalization, respectively). Hypoxia only slightly (by approximately 30%) increased the cell adhesion molecule ICAM-1 content on the cell surface, whereas reoxygenation more than doubled its expression. The reoxygenation effect depended on the medium acidity, and ICAM-1 increase was more pronounced at pH 7.0 compared to that at pH 6.4 and 7.4. Neither hypoxia nor reoxygenation induced expression of two other cell adhesion molecules, VCAM and E-selectin. Incubation of cells under hypoxic conditions but not reoxygenation stimulated secretion of von Willebrand factor and increased its concentration in the culture medium by more than 4 times. The percentage of cells containing apoptosis marker, activated caspase-3, was increased by approximately 1.5 times upon hypoxia as well as hypoxia/reoxygenation. Maximal values were achieved when reoxygenation was performed at pH 7.0. These data show that hypoxia/reoxygenation stimulate pro-inflammatory activation (ICAM-1 expression) and apoptosis (caspase-3 activation) of endothelial cells, and the extracellular pH influences both processes.
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Affiliation(s)
- O A Antonova
- Russian Cardiology Research and Production Complex, Moscow, 121552, Russia
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25
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Babich V, Knipe L, Hewlett L, Meli A, Dempster J, Hannah MJ, Carter T. Differential effect of extracellular acidosis on the release and dispersal of soluble and membrane proteins secreted from the Weibel-Palade body. J Biol Chem 2009; 284:12459-68. [PMID: 19258324 DOI: 10.1074/jbc.m809235200] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Proteins secreted from Weibel-Palade bodies (WPBs) play important roles in regulating inflammatory and hemostatic responses. Inflammation is associated with the extracellular acidification of tissues and blood, conditions that can alter the behavior of secreted proteins. The effect of extracellular pH (pH(o)) on the release of von Willebrand factor (VWF), the VWF-propolypeptide (Proregion), interleukin-8, eotaxin-3, P-selectin, and CD63 from WPBs was investigated using biochemical approaches and by direct optical analysis of individual WPB fusion events in human endothelial cells expressing green or red fluorescent fusions of these different cargo proteins. Between pH(o) 7.4 and 7.0, ionomycin-evoked WPB exocytosis was characterized by the adhesion of VWF to the cell surface and the formation of long filamentous strands. The rapid dispersal of Proregion, interleukin-8, and eotaxin-3 into solution, and of P-selectin and CD63 into the plasma membrane, was unaltered over this pH(o) range. At pH(o) 6.8 or lower, Proregion remained associated with VWF, in many cases WPB failed to collapse fully and VWF failed to form filamentous strands. At pH(o) 6.5 dispersal of interleukin-8, eotaxin-3, and the membrane protein CD63 remained unaltered compared with that at pH(o) 7.4; however, P-selectin dispersal into the plasma membrane was significantly slowed. Thus, extracellular acidification to levels of pH(o) 6.8 or lower significantly alters the behavior of secreted VWF, Proregion, and P-selectin while rapid release of the small pro-inflammatory mediators IL-8 and eotaxin-3 is essentially unaltered. Together, these data suggest that WPB exocytosis during extracellular acidosis may favor the control of inflammatory processes.
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Affiliation(s)
- Victor Babich
- MRC National Institute for Medical Research, Mill Hill, London NW7 1AA, United Kingdom
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López D, Rodríguez-Sinovas A, Agulló L, Inserte J, Cabestrero A, García-Dorado D. Acidic reoxygenation protects against endothelial dysfunction in rat aortic rings submitted to simulated ischemia. Am J Physiol Heart Circ Physiol 2008; 295:H2409-16. [PMID: 18931032 DOI: 10.1152/ajpheart.00409.2008] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Ischemia-reperfusion causes endothelial dysfunction. Prolongation of acidosis during initial cardiac reperfusion limits infarct size in animal models, but the effects of acidic reperfusion on vascular function are unknown. The present work analyzes the effects of acidic reoxygenation on vascular responses to different agonists in rat aortic rings. Arterial rings obtained from Sprague-Dawley rat aorta were placed in organ baths containing a Krebs solution oxygenated at 37 degrees C (pH 7.4). After equilibration (30 mN, 1 h), the effects of acidosis (pH 6.4) on aortic responses to acetylcholine and norepinephrine were initially assessed under normoxic conditions. Thereafter, the effects of acidosis during hypoxia (1 h) or reoxygenation on aortic responses to acetylcholine, norepinephrine, or sodium nitroprusside were analyzed and compared with those observed in control rings. Acidosis did not modify aortic responses to acetylcholine or adrenaline during normoxia. In contrast, rings submitted to hypoxia and reoxygenated at pH 7.4 showed a reduction in vasodilator responses to acetylcholine and in contractions to norepinephrine with no change in responses to sodium nitroprusside. Reoxygenation at pH 6.4 did not modify the depressed response to norepinephrine but enhanced the recovery of acetylcholine-induced vasorelaxation. Cumulative concentration-response curves to acetylcholine showed an increased responsiveness to this drug in rings reoxygenated at a low pH. This functional improvement was associated with the preservation of aortic cGMP content after stimulation of reoxygenated rings with acetylcholine. In conclusion, acidic reoxygenation preserves endothelial function in arterial rings submitted to simulated ischemia, likely through the preservation of cGMP signaling.
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Affiliation(s)
- Diego López
- Laboratorio de Cardiología Experimental, Servicio de Cardiologia, Hospital Universitario Vall d'Hebron, Barcelona, Spain
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Hudlická O, Garnham A, Shiner R, Egginton S. Attenuation of changes in capillary fine structure and leukocyte adhesion improves muscle performance following chronic ischaemia in rats. J Physiol 2008; 586:4961-75. [PMID: 18755748 DOI: 10.1113/jphysiol.2008.158055] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Acute ischaemia-reperfusion disrupts capillary fine structure and increases leukocyte adhesion in postcapillary venules. We determined whether chronic muscle ischaemia has similar consequences, and whether it is possible to ameliorate its effect on muscle performance. Following ischaemia (unilateral ligation, common iliac artery) rat hindlimb muscles were examined without other intervention or following treatment with an xanthine oxidase inhibitor (allopurinol), a Na(+)/H(+) exchange blocker (amiloride), or an oxygen free radical scavenger (vitamin E). No significant leukocyte adhesion or rolling, nor changes in capillary fine structure were observed 3 days postsurgery, when limb use was limited. However, leukocyte rolling and adhesion almost trebled by 7 days (P < 0.001), when normal gait was largely restored. Capillary fine structure was disturbed over a similar time course, e.g. relative endothelial volume (control 46%, 7 days 61%; P < 0.05), that resolved by 5 weeks. Where activity was increased by mild electrical stimulation 3 days after ligation muscles showed enhanced capillary swelling (endothelial volume 66% versus 50%, P < 0.005), but improved fatigue index (52% versus 16%, P < 0.001) as a result of greater blood flow. Muscle fatigue after ligation was related to the extent of contraction-induced hyperaemia (R(2) = 0.725), but not capillary swelling. Amiloride, and to a lesser extent allopurinol but not vitamin E, significantly decreased leukocyte rolling and adhesion, as well as capillary endothelial swelling. We conclude that increased activity of ischaemic muscles on recovery is likely to accentuate acidosis accompanying changes in microcirculation and contribute to enhanced muscle fatigue, whereas formation of oxygen free radicals may be attenuated by endogenous protective mechanisms.
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Affiliation(s)
- O Hudlická
- Department of Physiology, University of Birmingham Medical School, Birmingham, UK
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Sodium/hydrogen exchange inhibition with cariporide reduces leukocyte adhesion via P-selectin suppression during inflammation. Br J Pharmacol 2008; 153:1678-85. [PMID: 18332863 DOI: 10.1038/sj.bjp.0707647] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND AND PURPOSE The Na(+)/H(+) exchange (NHE) inhibitor cariporide is known to ameliorate ischaemia/reperfusion (I/R) injury by reduction of cytosolic Ca(2+) overload. Leukocyte activation and infiltration also mediates I/R injury but whether cariporide reduces I/R injury by affecting leukocyte activation is unknown. We studied the effect of cariporide on thrombin and I/R induced leukocyte activation and infiltration models and examined P-selectin expression as a potential mechanism for any identified effects. EXPERIMENTAL APPROACH An in vivo rat mesenteric microcirculation microscopy model was used with stimulation by thrombin (0.5 micro ml(-1)) superfusion or ischaemia (by haemorrhagic shock for 60 min) and reperfusion (90 min). KEY RESULTS Treatment with cariporide (10 mg kg(-1) i.v.) significantly reduced leukocyte rolling, adhesion and extravasation after thrombin exposure. Similarly, cariporide reduced leukocyte rolling (54+/-6.2 to 2.4+/-1.0 cells min(-1), P<0.01), adherence (6.3+/-1.9 to 1.2+/-0.4 cells 100 microm(-1), P<0.01) and extravasation (9.1+/-2.1 to 2.4+/-1.1 cells per 20 x 100 microm perivascular space, P<0.05), following haemorrhagic shock induced systemic ischaemia and reperfusion. The cell adhesion molecule P-selectin showed a profound decrease in endothelial expression following cariporide administration in both thrombin and I/R stimulated groups (35.4+/-3.2 vs 14.2+/-4.1% P-selectin positive cells per tissue section, P<0.01). CONCLUSIONS AND IMPLICATIONS The NHE inhibitor cariporide is known to limit reperfusion injury by controlling Ca(2+) overload but these data are novel evidence for a vasculoprotective effect of NHE inhibition at all levels of leukocyte activation, an effect which is likely to be mediated at least in part by a reduction of P-selectin expression.
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